<template>
  <view class="u-upload" :style="[$u.addStyle(customStyle)]">
    <view class="u-upload__wrap">
      <template v-if="previewImage">
        <view class="u-upload__wrap__preview" v-for="(item, index) in lists" :key="index">
          <image
            v-if="item.isImage || (item.type && item.type === 'image')"
            :src="item.thumb || item.url"
            :mode="imageMode"
            class="u-upload__wrap__preview__image"
            @tap="onPreviewImage(item)"
            :style="[
              {
                width: $u.addUnit(width),
                height: $u.addUnit(height),
              },
            ]"
          />
          <view v-else class="u-upload__wrap__preview__other">
            <u-icon
              color="#80CBF9"
              size="26"
              :name="
                item.isVideo || (item.type && item.type === 'video') ? 'movie' : 'folder'
              "
            ></u-icon>
            <text class="u-upload__wrap__preview__other__text">{{
              item.isVideo || (item.type && item.type === "video") ? "视频" : "文件"
            }}</text>
          </view>
          <view
            class="u-upload__status"
            v-if="item.status === 'uploading' || item.status === 'failed'"
          >
            <view class="u-upload__status__icon">
              <u-icon
                v-if="item.status === 'failed'"
                name="close-circle"
                color="#ffffff"
                size="25"
              />
              <u-loading-icon size="22" mode="circle" color="#ffffff" v-else />
            </view>
            <text v-if="item.message" class="u-upload__status__message">{{
              item.message
            }}</text>
          </view>
          <view
            class="u-upload__deletable"
            v-if="item.status !== 'uploading' && (deletable || item.deletable)"
            @tap.stop="deleteItem(index)"
          >
            <view class="u-upload__deletable__icon">
              <u-icon name="close" color="#ffffff" size="10"></u-icon>
            </view>
          </view>
          <view class="u-upload__success" v-if="item.status === 'success'">
            <!-- #ifdef APP-NVUE -->
            <image :src="successIcon" class="u-upload__success__icon"></image>
            <!-- #endif -->
            <!-- #ifndef APP-NVUE -->
            <view class="u-upload__success__icon">
              <u-icon name="checkmark" color="#ffffff" size="12"></u-icon>
            </view>
            <!-- #endif -->
          </view>
        </view>
      </template>

      <template v-if="isInCount">
        <view v-if="$slots.default || $slots.$default" @tap="chooseFile">
          <slot />
        </view>
        <view
          v-else
          class="u-upload__button"
          :hover-class="!disabled ? 'u-upload__button--hover' : ''"
          hover-stay-time="150"
          @tap="chooseFile"
          :class="[disabled && 'u-upload__button--disabled']"
          :style="[
            {
              width: $u.addUnit(width),
              height: $u.addUnit(height),
            },
          ]"
        >
          <u-icon :name="uploadIcon" :size="iconSize" :color="uploadIconColor"></u-icon>
          <text v-if="uploadText" class="u-upload__button__text">{{ uploadText }}</text>
        </view>
      </template>
    </view>
  </view>
</template>

<script>
import { chooseFile } from "./utils";
import mixin from "./mixin.js";
import props from "./props.js";

/**
 * upload 上传
 * @description 该组件用于上传图片场景
 * @tutorial https://uviewui.com/components/upload.html
 * @property {String}			accept				接受的文件类型, 可选值为all media image file video （默认 'image' ）
 * @property {String | Array}	capture				图片或视频拾取模式，当accept为image类型时设置capture可选额外camera可以直接调起摄像头（默认 ['album', 'camera'] ）
 * @property {Boolean}			compressed			当accept为video时生效，是否压缩视频，默认为true（默认 true ）
 * @property {String}			camera				当accept为video时生效，可选值为back或front（默认 'back' ）
 * @property {Number}			maxDuration			当accept为video时生效，拍摄视频最长拍摄时间，单位秒（默认 60 ）
 * @property {String}			uploadIcon			上传区域的图标，只能内置图标（默认 'camera-fill' ）
 * @property {Number | String}		iconSize			上传区域的图标大小，单位px（默认 26 ）
 * @property {String}			uploadIconColor		上传区域的图标的字体颜色，只能内置图标（默认 #D3D4D6 ）
 * @property {Boolean}			useBeforeRead		是否开启文件读取前事件（默认 false ）
 * @property {Boolean}			previewFullImage	是否显示组件自带的图片预览功能（默认 true ）
 * @property {String | Number}	maxCount			最大上传数量（默认 52 ）
 * @property {Boolean}			disabled			是否启用（默认 false ）
 * @property {String}			imageMode			预览上传的图片时的裁剪模式，和image组件mode属性一致（默认 'aspectFill' ）
 * @property {String}			name				标识符，可以在回调函数的第二项参数中获取
 * @property {Array}			sizeType			所选的图片的尺寸, 可选值为original compressed（默认 ['original', 'compressed'] ）
 * @property {Boolean}			multiple			是否开启图片多选，部分安卓机型不支持 （默认 false ）
 * @property {Boolean}			deletable			是否展示删除按钮（默认 true ）
 * @property {String | Number}	maxSize				文件大小限制，单位为byte （默认 Number.MAX_VALUE ）
 * @property {Array}			fileList			显示已上传的文件列表
 * @property {String}			uploadText			上传区域的提示文字
 * @property {String | Number}	width				内部预览图片区域和选择图片按钮的区域宽度（默认 80 ）
 * @property {String | Number}	height				内部预览图片区域和选择图片按钮的区域高度（默认 80 ）
 * @property {Object}			customStyle			组件的样式，对象形式
 * @event {Function} afterRead		读取后的处理函数
 * @event {Function} beforeRead		读取前的处理函数
 * @event {Function} oversize		文件超出大小限制
 * @event {Function} clickPreview	点击预览图片
 * @event {Function} delete 		删除图片
 * @example <u-upload :action="action" :fileList="fileList" ></u-upload>
 */
export default {
  name: "u-upload",
  mixins: [uni.$u.mpMixin, uni.$u.mixin, mixin, props],
  data() {
    return {
      // #ifdef APP-NVUE
      successIcon:
        "",
      // #endif
      lists: [],
      isInCount: true,
    };
  },
  watch: {
    // 监听文件列表的变化，重新整理内部数据
    fileList: {
      immediate: true,
      handler() {
        this.formatFileList();
      },
    },
  },
  methods: {
    formatFileList() {
      const { fileList = [], maxCount } = this;
      const lists = fileList.map((item) =>
        Object.assign(Object.assign({}, item), {
          // 如果item.url为本地选择的blob文件的话，无法判断其为video还是image，此处优先通过accept做判断处理
          isImage: this.accept === "image" || uni.$u.test.image(item.url || item.thumb),
          isVideo: this.accept === "video" || uni.$u.test.video(item.url || item.thumb),
          deletable:
            typeof item.deletable === "boolean" ? item.deletable : this.deletable,
        })
      );
      this.lists = lists;
      this.isInCount = lists.length < maxCount;
    },
    chooseFile() {
      const { maxCount, multiple, lists, disabled } = this;
      if (disabled) return;
      // 如果用户传入的是字符串，需要格式化成数组
      let capture;
      try {
        capture = uni.$u.test.array(this.capture)
          ? this.capture
          : this.capture.split(",");
      } catch (e) {
        capture = [];
      }
      chooseFile(
        Object.assign(
          {
            accept: this.accept,
            multiple: this.multiple,
            capture: capture,
            compressed: this.compressed,
            maxDuration: this.maxDuration,
            sizeType: this.sizeType,
            camera: this.camera,
          },
          {
            maxCount: maxCount - lists.length,
          }
        )
      )
        .then((res) => {
          this.onBeforeRead(multiple ? res : res[0]);
        })
        .catch((error) => {
          this.$emit("error", error);
        });
    },
    // 文件读取之前
    onBeforeRead(file) {
      const { beforeRead, useBeforeRead } = this;
      let res = true;
      // beforeRead是否为一个方法
      if (uni.$u.test.func(beforeRead)) {
        // 如果用户定义了此方法，则去执行此方法，并传入读取的文件回调
        res = beforeRead(file, this.getDetail());
      }
      if (useBeforeRead) {
        res = new Promise((resolve, reject) => {
          this.$emit(
            "beforeRead",
            Object.assign(
              Object.assign(
                {
                  file,
                },
                this.getDetail()
              ),
              {
                callback: (ok) => {
                  ok ? resolve() : reject();
                },
              }
            )
          );
        });
      }
      if (!res) {
        return;
      }
      if (uni.$u.test.promise(res)) {
        res.then((data) => this.onAfterRead(data || file));
      } else {
        this.onAfterRead(file);
      }
    },
    getDetail(index) {
      return {
        name: this.name,
        index: index == null ? this.fileList.length : index,
      };
    },
    onAfterRead(file) {
      const { maxSize, afterRead } = this;
      const oversize = Array.isArray(file)
        ? file.some((item) => item.size > maxSize)
        : file.size > maxSize;
      if (oversize) {
        this.$emit(
          "oversize",
          Object.assign(
            {
              file,
            },
            this.getDetail()
          )
        );
        return;
      }
      if (typeof afterRead === "function") {
        afterRead(file, this.getDetail());
      }
      this.$emit(
        "afterRead",
        Object.assign(
          {
            file,
          },
          this.getDetail()
        )
      );
    },
    deleteItem(index) {
      this.$emit(
        "delete",
        Object.assign(Object.assign({}, this.getDetail(index)), {
          file: this.fileList[index],
        })
      );
    },
    // 预览图片
    onPreviewImage(item) {
      if (!item.isImage || !this.previewFullImage) return;
      uni.previewImage({
        // 先filter找出为图片的item，再返回filter结果中的图片url
        urls: this.lists
          .filter(
            (item) => this.accept === "image" || uni.$u.test.image(item.url || item.thumb)
          )
          .map((item) => item.url || item.thumb),
        current: item.url || item.thumb,
        fail() {
          uni.$u.toast("预览图片失败");
        },
      });
    },
    onPreviewVideo(event) {
      if (!this.data.previewFullImage) return;
      const { index } = event.currentTarget.dataset;
      const { lists } = this.data;
      wx.previewMedia({
        sources: lists
          .filter((item) => isVideoFile(item))
          .map((item) =>
            Object.assign(Object.assign({}, item), {
              type: "video",
            })
          ),
        current: index,
        fail() {
          uni.$u.toast("预览视频失败");
        },
      });
    },
    onClickPreview(event) {
      const { index } = event.currentTarget.dataset;
      const item = this.data.lists[index];
      this.$emit(
        "clickPreview",
        Object.assign(Object.assign({}, item), this.getDetail(index))
      );
    },
  },
};
</script>

<style lang="scss" scoped>
@import "../../libs/css/components.scss";
$u-upload-preview-border-radius: 2px !default;
$u-upload-preview-margin: 0 8px 8px 0 !default;
$u-upload-image-width: 80px !default;
$u-upload-image-height: $u-upload-image-width;
$u-upload-other-bgColor: rgb(242, 242, 242) !default;
$u-upload-other-flex: 1 !default;
$u-upload-text-font-size: 11px !default;
$u-upload-text-color: $u-tips-color !default;
$u-upload-text-margin-top: 2px !default;
$u-upload-deletable-right: 0 !default;
$u-upload-deletable-top: 0 !default;
$u-upload-deletable-bgColor: rgb(55, 55, 55) !default;
$u-upload-deletable-height: 14px !default;
$u-upload-deletable-width: $u-upload-deletable-height;
$u-upload-deletable-boder-bottom-left-radius: 100px !default;
$u-upload-deletable-zIndex: 3 !default;
$u-upload-success-bottom: 0 !default;
$u-upload-success-right: 0 !default;
$u-upload-success-border-style: solid !default;
$u-upload-success-border-top-color: transparent !default;
$u-upload-success-border-left-color: transparent !default;
$u-upload-success-border-bottom-color: $u-success !default;
$u-upload-success-border-right-color: $u-upload-success-border-bottom-color;
$u-upload-success-border-width: 9px !default;
$u-upload-icon-top: 0px !default;
$u-upload-icon-right: 0px !default;
$u-upload-icon-h5-top: 1px !default;
$u-upload-icon-h5-right: 0 !default;
$u-upload-icon-width: 16px !default;
$u-upload-icon-height: $u-upload-icon-width;
$u-upload-success-icon-bottom: -10px !default;
$u-upload-success-icon-right: -10px !default;
$u-upload-status-right: 0 !default;
$u-upload-status-left: 0 !default;
$u-upload-status-bottom: 0 !default;
$u-upload-status-top: 0 !default;
$u-upload-status-bgColor: rgba(0, 0, 0, 0.5) !default;
$u-upload-status-icon-Zindex: 1 !default;
$u-upload-message-font-size: 12px !default;
$u-upload-message-color: #ffffff !default;
$u-upload-message-margin-top: 5px !default;
$u-upload-button-width: 80px !default;
$u-upload-button-height: $u-upload-button-width;
$u-upload-button-bgColor: rgb(244, 245, 247) !default;
$u-upload-button-border-radius: 2px !default;
$u-upload-botton-margin: 0 8px 8px 0 !default;
$u-upload-text-font-size: 11px !default;
$u-upload-text-color: $u-tips-color !default;
$u-upload-text-margin-top: 2px !default;
$u-upload-hover-bgColor: rgb(230, 231, 233) !default;
$u-upload-disabled-opacity: 0.5 !default;

.u-upload {
  @include flex(column);
  flex: 1;

  &__wrap {
    @include flex;
    flex-wrap: wrap;
    flex: 1;

    &__preview {
      border-radius: $u-upload-preview-border-radius;
      margin: $u-upload-preview-margin;
      position: relative;
      overflow: hidden;
      @include flex;

      &__image {
        width: $u-upload-image-width;
        height: $u-upload-image-height;
      }

      &__other {
        width: $u-upload-image-width;
        height: $u-upload-image-height;
        background-color: $u-upload-other-bgColor;
        flex: $u-upload-other-flex;
        @include flex(column);
        justify-content: center;
        align-items: center;

        &__text {
          font-size: $u-upload-text-font-size;
          color: $u-upload-text-color;
          margin-top: $u-upload-text-margin-top;
        }
      }
    }
  }

  &__deletable {
    position: absolute;
    top: $u-upload-deletable-top;
    right: $u-upload-deletable-right;
    background-color: $u-upload-deletable-bgColor;
    height: $u-upload-deletable-height;
    width: $u-upload-deletable-width;
    @include flex;
    border-bottom-left-radius: $u-upload-deletable-boder-bottom-left-radius;
    align-items: center;
    justify-content: center;
    z-index: $u-upload-deletable-zIndex;

    &__icon {
      position: absolute;
      transform: scale(0.7);
      top: $u-upload-icon-top;
      right: $u-upload-icon-right;
      /* #ifdef H5 */
      top: $u-upload-icon-h5-top;
      right: $u-upload-icon-h5-right;
      /* #endif */
    }
  }

  &__success {
    position: absolute;
    bottom: $u-upload-success-bottom;
    right: $u-upload-success-right;
    @include flex;
    // 由于weex(nvue)为阿里巴巴的KPI(部门业绩考核)的laji产物，不支持css绘制三角形
    // 所以在nvue下使用图片，非nvue下使用css实现
    /* #ifndef APP-NVUE */
    border-style: $u-upload-success-border-style;
    border-top-color: $u-upload-success-border-top-color;
    border-left-color: $u-upload-success-border-left-color;
    border-bottom-color: $u-upload-success-border-bottom-color;
    border-right-color: $u-upload-success-border-right-color;
    border-width: $u-upload-success-border-width;
    align-items: center;
    justify-content: center;
    /* #endif */

    &__icon {
      /* #ifndef APP-NVUE */
      position: absolute;
      transform: scale(0.7);
      bottom: $u-upload-success-icon-bottom;
      right: $u-upload-success-icon-right;
      /* #endif */
      /* #ifdef APP-NVUE */
      width: $u-upload-icon-width;
      height: $u-upload-icon-height;
      /* #endif */
    }
  }

  &__status {
    position: absolute;
    top: $u-upload-status-top;
    bottom: $u-upload-status-bottom;
    left: $u-upload-status-left;
    right: $u-upload-status-right;
    background-color: $u-upload-status-bgColor;
    @include flex(column);
    align-items: center;
    justify-content: center;

    &__icon {
      position: relative;
      z-index: $u-upload-status-icon-Zindex;
    }

    &__message {
      font-size: $u-upload-message-font-size;
      color: $u-upload-message-color;
      margin-top: $u-upload-message-margin-top;
    }
  }

  &__button {
    @include flex(column);
    align-items: center;
    justify-content: center;
    width: $u-upload-button-width;
    height: $u-upload-button-height;
    background-color: $u-upload-button-bgColor;
    border-radius: $u-upload-button-border-radius;
    margin: $u-upload-botton-margin;
    /* #ifndef APP-NVUE */
    box-sizing: border-box;
    /* #endif */

    &__text {
      font-size: $u-upload-text-font-size;
      color: $u-upload-text-color;
      margin-top: $u-upload-text-margin-top;
    }

    &--hover {
      background-color: $u-upload-hover-bgColor;
    }

    &--disabled {
      opacity: $u-upload-disabled-opacity;
    }
  }
}
</style>
